1. Field of the Invention
The present invention pertains to card carriers such as wallets, and in particular to card carriers having means for indicating when a card is absent from the card carrier.
2. Description of Related Art
The advent of the credit card has revolutionized the manner in which consumer transactions are conducted. Credit card usage has become so pervasive that purchases of goods and services by credit card have become the preferred form of monetary transfer for many businesses and consumers. Purchases by credit card have become so popular in part because such purchases dispense with the need of the consumer to carry a considerable amount of cash. In addition, purchases by credit card have freed the consumer to make purchases on credit rather than deplete his or her existing cash resources.
Credit card usage, however, is not without its attendant drawbacks and risks. For example, in retail transactions involving the use of the card to make a purchase or to verify one's identification (such as is oftentimes required to write a check), the card is typically removed from the wallet and given to a salesperson. It is not uncommon during the course of such a transaction for the credit card to become misplaced or inadvertently left at the sales counter. The frequency of such occurrences increases in busy retail establishments, especially during the holidays. The failure of the owner to return the card to his or her wallet oftentimes goes unnoticed until she or he subsequently attempts to make another credit card-based transaction. The subsequent discovery of the absence of the credit card is both a nuisance to the card owner, who is unable in many instances to make the desired purchase, and a cause for concern, for the owner may not be able to readily recall where the card was left. Accordingly, it is desirable to provide a card carrier having a warning device which notifies the card owner of the absence of the card following completion of the credit transaction.
Wallets having alarms for indicating the absence of a credit card are known in the art. For example, U.S. Pat. No. 4,480,250 to McNeely discloses a credit card carrier, such as a wallet, which includes a pair of flaps foldable upon one another. Each of the flaps includes a plurality of clip switches arranged for receiving credit cards. The clip switches are arranged in parallel interconnection with one another, and in series interconnection between a battery and an alarm. When a credit card is removed from one of the clip switches, the circuit between the battery and the alarm is completed and the alarm is energized. The flaps include a proximity switch, such as a magnetic reed switch, which disables the alarm when the flaps are in an open position or, alternatively, enables the alarm circuit only when the flaps are folded upon each other. However, McNeely's alarm is triggered only when a card is missing from a pocket and the flaps are folded together. This arrangement suffers from the disadvantage that the alarm signal indicating the absence of a card is dependent upon the relative position of the wallet flaps. This dependency is not reliable in instances where the wallet is stored in a relatively large enclosure such as a purse having numerous other items stored therein which could prevent the flaps from coming together to complete the alarm circuit. In addition, a reed switch is mechanical and by its very nature is subject to failure or at least possible erratic behavior.
Another example of a credit card wallet alarm device is disclosed in U.S. Pat. No. 3,959,789 to McGahee. This patent discloses a check or credit card monitor consisting of a plurality of normally closed switches adapted to be held open by insertion of credit cards or similar items between the switch contacts. The contacts are connected in parallel to a timing mechanism adapted to energize a sensory alarm such as an audio signal, vibrator or light a predetermined time after closure of any one of the plurality of switches. Switch closure occurs upon the removal of the check or credit card from the monitor. This alarm arrangement, however, is not desirable because the alarm will sound during sales transactions in which the card is removed from the carrier for a period of time in excess of the predetermined time interval of the alarm circuit, thereby increasing the occurrence of false triggering of the alarm.
Other devices are known in the art which are designed to detect when an article has been accidentally lost or stolen. For example, U.S. Pat. No. 4,558,307 to Lienart discloses a reminder device which includes a photosensitive cell secured within a container. The container may be secured to an object such as a wallet in order to prevent accidental loss thereof. An electronic circuit is connected to the photosensitive cell and is fed by an electrical signal produced by the cell when the cell is irradiated by ambient light. The electronic circuit includes a delay circuit adapted to receive the signal and arranged to produce a control signal when the cell has been irradiated for a predetermined time interval. The electronic circuit is coupled to an audible signal generator which produces an audible alarm in response to the control signal. Because this device provides for the generation of an alarm signal after a predetermined time interval has passed, it, too is unsuitable for general use due to its susceptibility to trigger false alarm signals. Also, while perhaps being useful to detect loss of a whole wallet, this device would be impractical for detecting loss of an object such as a credit card since, among other reasons, it would be too bulky to attach to a credit card.
A self actuating wallet alarm is disclosed in U.S. Pat. No. 3,930,249 to Steck et al. The wallet includes an electronic circuit that emits an audible alarm when the wallet is removed from an owner's purse or pocket, and is designed to guard against pickpockets. The electronic circuit is coupled to an externally mounted photosensor which produces an electrical signal which drives the circuit and an alarm coupled thereto upon exposure of the photosensor to ambient light. When the photosensor is exposed to light below a predetermined threshold, such as when the wallet is included in an enclosure such as a pocket or purse, no electrical signal is generated for driving the circuit and the alarm. For reasons discussed above with respect to Lienart, using photocells attached to credit cards to detect their removal is impractical since the size requirements for credit cards prohibit attachment of photocells and associated circuitry thereto. Further, credit cards are frequently removed from wallets during ordinary use, and it makes no sense to have a photocell sound an alarm every time a credit card is removed.
As is evident from the above discussion of the related art, the known card carriers and other devices are unsuited to the demands and circumstances surrounding many credit card transactions consumers today contend with.